Originally posted by peterpan73
Those PCBs look fab..... and I am impressed...and excited too. By the way, I still don't know wyy I haven't received the Titan 2000 part two and three. I guess my mailbox is not allowing it. Tarun have you tried...

I've asked my friend to send you the files. I couldn't send them because Yahoo does not allow the sender to attach a file larger than 3MB (after encoding). My friend sent you the file (part 2) in front of me, about ten days ago. He has not received any reply from you after that, so I assumed you've received it.

Quote:

Another thing. I am looking for heatsinks. Those long large ones with large fins. I asked Visha and Gala but no replies. Size and type - well large enuf for the Titan 2000. Can anyone here give me a ballpark figure to help me fix a budget for these amps.

I have used long large ones with fins, black anodised. One section I've seen has a base 100mm wide, and base-to-fin height of about 32mm. This one is about Rs.16 per cm length. A piece 12 inches long will then be about Rs.450-480 or so. There's another section with longer, more slender fins, which is about Rs.20 per cm, I think. Their biggest section has a base about seven and a half inches wide, and fins of about 25-30mm height. That one is between Rs.25 and 30 per cm.

As always, Angshu buys foot-long heatsinks from Delhi, black anodised, for Rs.100, at a fraction of what I buy them for. And I don't know what you mean by "no replies", because Visha and Precious both stock heatsinks, and I've bought at least half a dozen large heatsinks from Visha by now.

I used whatever contacts I had to contact Peerless India. I reached a certain Mr.Ajay, who I think is part of the team that manages the company. I had one phone conversation with him. He was very courteous, and patiently answered all my questions. The gist of what he said:

They are totally independent of Peerless Denmark. Therefore, if there's a speaker model on the Peerless Denmark Website, don't even ask Peerless India about it, because there is no connection between the two. Good to hear it from the horse's mouth. Therefore, henceforth, please do not speculate about why there is a Danish-sounding word (Fabrikkerne) in the HTML title of the index page of their Website, or why they mention "Danish technology" when talking about their work on their homepage. Just don't.

They make speakers for large orders only. They don't have any process or mechanism to sell to retailers directly.

The models contained on their Website are all, in a sense, a sample showcase. They don't have any connection to models in manufacture right now. Therefore, don't pick a model from their Website and ask them "can I buy four of those?" They may not have made that model in the last five years. I guess their Website just serves as a kind of showcase of capabilities for their customers who place job-work orders on them.

Now the nice part. There is one gentleman, Jeetubhai, who has a cellphone (98211 61535) on which you can call him. He picks up the surplus stock of any production runs that Peerless India may have, and sells them in the local market. This means, of course, that a particular model of driver may be available once from Jeetubhai, and never again if you look a few years later. It's a seller's market, and since no model or brand loyalty is being set up for the Indian buyer, there is no commitment to re-supply the same items. But if you want 'em, you can have 'em, from Jeetu bhai.

If you want to know what Peerless India drivers are available, it is best that you contact Jeetubhai, not Peerless India. Because it's Jeetubhai's stock which you will get. And if, after you get a model from him, you want to know what the T/S parameters for it are, you can call Mr.Ajay. I forget his phone number, but I can find out. Or I guess you can find out from Jeetubhai.
I specifically asked him "Won't it be a bother if I and some of my friends begin calling you up and asking you the details of some driver or other? Can you give me a pointer to someone else in your office?" And he clearly said, "No, that's not a problem. Actually, no one else in my office will know about these things, and I can afford to take these calls, so please ask your friends to call me." Very nice of him.

That, in short is the Peerless story. According to Ajay, all Peerless India drivers available anywhere in Lamington Road are all from Jeetubhai and Jeetubhai alone. Apparently Chaudhury Trading used to stock these drivers directly from Peerless India, but does not do so any more.

Ajay had heard of Madisound.com, and shared my lament at the tiny or non-existent local market for good components for DIY and amateur builders in India. Ah, well, at least he's heard of Madisound.

I met Mr.Valecha yesterday, and checked with him about getting a very small quantity of custom-made knobs made. I was discussing the possibility of getting something like 20 knobs, each of 50mm or 63mm diameter (i.e. cut from 2" or 2.5" bar stock), maybe 1" or 1.5" tall, and finished in hard anodised clear aluminium colour, with a fine grainy texture (looks like matte finish, not the hard shiny metallic finish). Internal shaft diameter of 6mm or 6.2mm (quarter-inch). He can't give me a price yet, but it'll probably be of the order of Rs.300 each. Very rough estimate.

I've seen the finish of one of his other knobs, which he has a stock of about a hundred of (I'd written about this knob in an earlier post.) I was asking him about getting the new knobs made to have the same finish as those ones, so that I could use the custom-made big knob for a volume control and the smaller ones for everything else (input selector, balance, tone controls). They'd have identical appearance, surface texture, colour and finish.

Would you guys be interested in such knobs? If you've ever looked for very well-made good knobs, you know how hard they are to find, worldwide. I can go ahead only if I get some others to pool in. I have no need for 20 knobs just for myself, and all my DIY friends here put together will probably be able to absorb five or six of these, not more.

Tarun

PS: He has about a hundred of the smaller knobs with him. I'm picking up 20. You can ask him for the rest. He said he'll charge me Rs.40 per knob. Once I get them (tomorrow; they're being marked with a "dot" for a position marker now), I'll go looking for someone who can click a good picture of it, so that I can post it here. They're absolute beauties, with 6mm shaft diameters, finished as I described above.

Good find there knobs et al. Yes indeed.. why not I will definitely pool in if I like them first. I use these cheap plastic knobs for my homebrew live sound equipment and anything better is a yes yes!! So send me those pics and I'll send you the dough. About your long write up in PCB making and those great looking pics... well its not different from what I do chromolin film exposure, stencil making and squegee run down with non-etch inks, manual hole drilling.... but I skip the masking stage thats all. HOwever I must admit that Image's quality from the pics you've posted that we've seen is in my opinion apparently 30% better than what I can do at home - especially the solder masking. Would post the pics after I'm done with my amp project.

Quote:

I've asked my friend to send you the files. I couldn't send them because Yahoo does not allow the sender to attach a file larger than 3MB (after encoding). My friend sent you the file (part 2) in front of me, about ten days ago. He has not received any reply from you after that, so I assumed you've received it.

You didnt mention to which account. If its the sddigiconsolution.com account then I will have to wait as the email servers are being cleaned up or so I'm told by my ISP till next month, if its the mickeyevents.com account then OK I will have to ask my hosting Inc how I can retrieve mail from there. If its into yahoo which I check everyday and most user friendly of all then I simply haven't got it yet. So please let me know which one. Anyways thats for the great effort mate.

Quote:

And I don't know what you mean by "no replies", because Visha and Precious both stock heatsinks, and I've bought at least half a dozen large heatsinks from Visha by now.

If that is true, then it only sums up to one other thing- they dont sell out station or the emails and snail mail I sent did'nt reach them.

Quote:

As always, Angshu buys foot-long heatsinks from Delhi, black anodised, for Rs.100, at a fraction of what I buy them for.

Hey Angshu ... he let the cat out of the bag.. if thats true then you have to help me get them or at the very least point me to those who can .... by mail order!! Hey I don't mind paying a bit extra for all that hardwork OK!! I understand you will have to lose time not to mention money in getting those things for me.Is that from Lajpat Rai Market, Bhagirath Palace kinda locale.??

I hope you guys here can empathise with my problems I am so fed up with my water cooled heatsinks.... they take a lot of time (and money) to make and I have to invest on a lot of equipment to get my DIY going.

Patrick

__________________
Thinking is the Hardest Work there is. Which is the probable reason why so few engage in it.

Good find there knobs et al. Yes indeed.. why not I will definitely pool in if I like them first. I use these cheap plastic knobs for my homebrew live sound equipment and anything better is a yes yes!! So send me those pics and I'll send you the dough. About your long write up in PCB making and those great looking pics... well its not different from what I do chromolin film exposure, stencil making and squegee run down with non-etch inks, manual hole drilling.... but I skip the masking stage thats all. HOwever I must admit that Image's quality from the pics you've posted that we've seen is in my opinion apparently 30% better than what I can do at home - especially the solder masking. Would post the pics after I'm done with my amp project.

Quote:

I've asked my friend to send you the files. I couldn't send them because Yahoo does not allow the sender to attach a file larger than 3MB (after encoding). My friend sent you the file (part 2) in front of me, about ten days ago. He has not received any reply from you after that, so I assumed you've received it.

You didnt mention to which account. If its the sddigiconsolution.com account then I will have to wait as the email servers are being cleaned up or so I'm told by my ISP till next month, if its the mickeyevents.com account then OK I will have to ask my hosting Inc how I can retrieve mail from there. If its into yahoo which I check everyday and most user friendly of all then I simply haven't got it yet. So please let me know which one. Anyways thats for the great effort mate!!

Quote:

And I don't know what you mean by "no replies", because Visha and Precious both stock heatsinks, and I've bought at least half a dozen large heatsinks from Visha by now.

If that is true, then it only sums up to one other thing- they dont sell out station or the emails and snail mail I sent did'nt reach them.

Quote:

As always, Angshu buys foot-long heatsinks from Delhi, black anodised, for Rs.100, at a fraction of what I buy them for.

Hey Angshu ... he let the cat out of the bag.. if thats true then you have to help me get them or at the very least point me to those who can .... by mail order!! Hey I don't mind paying a bit extra for all that hardwork OK!! I understand you will have to lose time not to mention money in getting those things for me.Is that from Lajpat Rai Market, Bhagirath Palace kinda locale.??
I hope you guys here can empathise with my problems I am so fed up with my water cooled heatsinks.... they take a lot of time (and money) to make and I have to invest on a lot of equipment to get my DIY going.
Patrick

__________________
Thinking is the Hardest Work there is. Which is the probable reason why so few engage in it.

I usually don't believe much in God, but today I saw Corrson's website, looked heavenward and cried "YES!!!". Mom and Dad thought I went crazy... Thank you so much, Tarun, Vivek and everyone else!

Anyway, here's one small contrib I can make to this: I remember seeing a box full of Philips "Class X" capacitors at a store called "Railton Electronics", SP Road, B'lore. Possibly worth a try. But then again, you have two alternatives:
a) Use caps meant for motor EMI suppression, they're rated for 230 V AC. I believe these are plastic film rolled capacitors.
b) Rely on the caps built into EMI suppression filters. You are using an EMI filter, aren't you? Elcom makes decent ones, including ones with an in-built IEC connector, fuse holder and (optional) switch, like what Peter Daniel has made here. Expensive, but I think they're worth it.

So has anyone located a vendor for 19" cabinets in B'lore? All I found so far is a firm called Texonic Instruments, which sells a 2U height 19" box, but in ABS! Their other products are very good, from a company called Gainta. Good for non-audio stuff (I used an ABS box for an AVR programmer and for a small headphone amp). I will be on the lookout for workshops where you can dump a heap of aluminium and tell them what to do with it. Where I work, the mechanical engg. division has some amazing (read: 5-axis! ) CNC milling/drilling machines, but I haven't worked there long enough to get friendly with the operators.

On the topic of PCBs, most electronics engineering students from blr would have heard of Om Electronics, which serves as a front to some dude who makes one- and two-sided PCBs. I've got several PCBs made from him, he requires a printout of the layout. I believe he tins the PCB by coating it with flux and dipping it in a solder pot, because it always has a lump of solder along one edge. He does glass epoxy boards at a small premium (~20 bucks for an average board). Charges are ~100 bucks for a 4"x2.5" Glass Epoxy single sided board, no solder mask. I gave him an order last week for a two-sided board with PTH, solder masking on both sides and silk-screen on one side. His quote was ~850 bucks so I dropped the silk screen layer to bump it down to 725. Still a lot, but I need the board to house two DSPs (AD1954... oh yeah! ) in TQFPs . The shop owner mentioned that the board cost is mostly for making films (four, in this case). He also mentioned that laser prints on transparency doesn't give sharp prints (which I've seen for myself). My DSP board uses track widths of 0.016" in some parts, and the TQFPs have a pitch of 0.025". Gulp! So far, I've only soldered SOICs.

Here's one source I'm not sure is as popular as it should be: SMD India. They operate out of an apartment in Shell Colony, Mumbai (boy did I have a hard time finding it in the rain!!!), and sell SMD components in small quantities. Why SMDs? Well, I dont know where you find E48 series resistors in leaded form, in quantities less than 500. These guys sell you E48 resistors (values like 3.74k) in small quantities (10 each). They also have C0G grade ceramic capacitors, useful for miller-compensation caps of power amps. C0G dielectric does not suffer from capacitance change with applied voltage or temperature. They also send stuff via courier, but I've never tried to ask them.

An aside: I met this guy at the SMDin shop/office/apartment, I forget his name, he seemed very interested in building miniature FM transmitters. Still in Engineering college. His enthu was kinda' inspiring. Just in case you're on DIYAudio, "Hey!"

Originally posted by roadkill
Anyway, here's one small contrib I can make to this: I remember seeing a box full of Philips "Class X" capacitors at a store called "Railton Electronics", SP Road, B'lore. Possibly worth a try. But then again, you have two alternatives:
a) Use caps meant for motor EMI suppression, they're rated for 230 V AC. I believe these are plastic film rolled capacitors.
b) Rely on the caps built into EMI suppression filters. You are using an EMI filter, aren't you? Elcom makes decent ones, including ones with an in-built IEC connector, fuse holder and (optional) switch, like what Peter Daniel has made here. Expensive, but I think they're worth it.

X-class caps are also available from universal electronics and Balaji electronics (which is next to UE). You'll have to try both because they don't have all the values. Incidentally, the last time I went to Balaji (about a year back IIRC) he said he had tubes! Didn't actually buy any, though.

Quote:

So has anyone located a vendor for 19" cabinets in B'lore? All I found so far is a firm called Texonic Instruments, which sells a 2U height 19" box, but in ABS! Their other products are very good, from a company called Gainta.

Where's Texonic located? Also on SP road?

Quote:

Where I work, the mechanical engg. division has some amazing (read: 5-axis! ) CNC milling/drilling machines, but I haven't worked there long enough to get friendly with the operators.

Great! Maybe once you're on good terms with them, certain Bangaloreans will try to get on good terms with you

Sorry for the double post... the message sent page didn't open up so i resent.
BTW .... are Neutrik Speak ons available in India? I have depleted my imported stock and need some more. A lot more.... by mail order.

Patrick

__________________
Thinking is the Hardest Work there is. Which is the probable reason why so few engage in it.

Originally posted by roadkill
... I remember seeing a box full of Philips "Class X" capacitors at a store called "Railton Electronics", SP Road, B'lore. Possibly worth a try.

Why not just get them from RS India? They charge less than Rs.40 each, and are rated at 440VAC, which is much more safe than something rated just 230VAC. Rod Elliott warns against using X caps rated at just 250VAC, somewhere in one of his articles.

And IEC sockets with fuse holders (and fuses, incidentally) are available from Champion Rubber Stores for Rs.17 each. I bought five the other day. They seem more than good enough for any purposes I may have, but they are not gold plated or uranium coated.

Quote:

I gave him an order last week for a two-sided board with PTH, solder masking on both sides and silk-screen on one side. His quote was ~850 bucks so I dropped the silk screen layer to bump it down to 725.

I think Rs.850 for a DSPTH board with solder masking and legend printing is superb if it's for small quantities. To present it in the right perspective, you'll have to subtract the one-time cost of the films, which, in this case, will probably be Rs.400 or so. That leaves just Rs.425 for the PCBs. Beats all the int'l prices deeply-hollow.

Quote:

He also mentioned that laser prints on transparency doesn't give sharp prints (which I've seen for myself). My DSP board uses track widths of 0.016" in some parts, and the TQFPs have a pitch of 0.025". Gulp! So far, I've only soldered SOICs.

Don't even think about using anything but the Gerber-plotted films when doing a PCB with track widths of 12mil or less, or pad pitch of less than, say, 0.67" (which is the gaps in the famous LM38xx audio amp chips). Calculations are simple. 10mil is, in a sense, 100dpi. To draw 12mil wide tracks with precise and straight edges, you'll need a printer with a resolution of at least 2mil, preferably 1mil or better. Most mainstream laser printers do 600dpi. 500dpi is 2mil, so 600dpi is approximately 2mil. With your printer having that as its limiting resolution, and your paper probably reducing it quite a bit due to ink smudging etc, you'll never get real accuracy of the kind you need for thin tracks. Therefore, I treat the limit for laser-printed PCB layouts as 16mil tracks, and if I push it, I can pass one such track between two legs of a DIP IC. For SOIC or SMD, you need to go Gerber. Gerber photoplotters have an accuracy of 1mil, I'm told, which means that their actual pixel resolution (if such a term can be used for them) is probaby 0.1mil.

I have not seen Tarun's heatsink, but I think they will have much lower thermal resistance than the 100 bucks heatsink I buy from Bhagirath place. These heatsinks are typically used in inverters etc. If you want I can send you some. I plan to measure it's thermal resistance sometime, but do not know when.

Afcoset in Bombay makes good heatsinks, but I cannot find then on the net. Long time back I used them a lot. They had a good catalog with termal resistance details. Tarun can you find out where they are hiding in Bombay.

PCB making.
Tarun's PCBs have come out really well I think the price is also very reasonable. I however feel the cost of film is bit high. If these guys accept bromides, them it will be good as I can get a pair of positive negative bromides made from block makers for 50 bucks. They accept 2x,4x plots so I do not think resolution should be any problem.

I have struggled a lot trying to make good home made PCBs, but finally settled for screen printing my self. I usually do single sided with legend printing, no solder mask. It's bit messy to do it at home, cleaning the screen is really a pain and time consuming, otherwise the final result is quite satisfying.

I take 1x images from my inkjet printer on translucent paper and it works pretty well.